The present invention relates to a shock-detecting apparatus for an industrial vehicle.
Japanese Patent Application Publication 2007-39213 discloses a shock-detecting apparatus for an industrial vehicle such as a forklift truck, having a shock-detecting sensor, a shock value computer, a judging device, a warning generator and a threshold value setting unit.
The shock-detecting sensor is a shock sensor fixed to an lifting device of a forklift truck so as to detect a shock acting on a cargo loaded on an lifting device and generate an output signal. Thus, the shock value computer receives the output signals sequentially thereby to compute the shock values respectively. The judging device judges whether or not the shock value is greater than a threshold value. When the judging device judges that the shock value is greater than the threshold value, the warning generator outputs a warning signal. The threshold value input unit allows a user to set an arbitrary threshold value at the initialization or any other time.
The conventional shock-detecting apparatus for the industrial vehicle as mentioned above compares the sequentially computed shock values with the threshold value sequentially while the forklift performs a loading operation and the like. When the shock value is judged to be greater than the threshold value, the warning generator outputs a warning signal with the result that the user of the forklift prevents damage to the cargo or the cargo collapse due to the excessive shock, and enables to perform the loading operation safe.
A proper range for the shock value acting on the industrial vehicle varies depending on where and how the industrial vehicle is used. Therefore, when the user installs the conventional shock-detecting apparatus with the industrial vehicle and sets the threshold value, he is apt to set the threshold value by trial and error. For example, after the user sets an arbitrary threshold value and operates the industrial vehicle actually, he may increase or decrease a threshold value so as to pursue the proper threshold value (trial and error) if wrong warning signals are output. This may bring about a decrease in reliability and it takes time to improve reliability after all. In this aspect, although Japanese Patent Application Publication 2007-39213 describes that the threshold value is decided based on the actual data operated by the experienced drivers, the concrete method to decide the threshold value is unclear and anyway it is still time-consuming to decide the threshold value.
The present invention is made to solve the above problems of the prior art and to provide a shock-detecting apparatus for an industrial vehicle which can facilitate to decide the threshold value.